The present invention relates to an apparatus and a method for mounting electronic components, which carry out a solvent transfer operation for transferring solvent such as flux, solder paste, or the like to electronic components requiring the transfer of the solvent at the time when the components are mounted to objects to be mounted such as boards or components.
Electronic component mounting apparatuses these days are required to mount electronic components speedily and correctly to electronic circuit boards, while improving mounting quality.
An example of a conventional electronic component mounting apparatus will be described below with reference to FIGS. 14, 15, and 16.
A conventional electronic component mounting apparatus 10 shown in FIG. 14 comprises a board transfer device 4 for carrying in and out circuit boards, a front component feed device 32a and a rear component feed device 32b each having a plurality of component feed units, a head part 6 with a mechanism that can load desired suction nozzles 8, move up and down, and rotate the loaded suction nozzles, a board recognition camera 9, an XY robot 5 movable in X and Y directions, an electronic component image pickup devices 2a, 2b, and a solvent transfer unit 40.
The above conventional electronic component mounting apparatus 10 operates in a manner as follows. The board transfer device 4 transfers a circuit board to a mounting position. The XY robot 5 moves the board recognition camera 9 over the circuit board thereby checking positions where electronic components are to be mounted on the circuit board. The XY robot 5 then moves the board recognition camera 9 over the front component feed device 32a and the rear component feed device 32b and recognizes components 33 to be caught. Subsequently, the XY robot 5 lets the nozzles 8 hold the electronic components 33. The electronic components 33 sucked and held by the nozzles 8 are moved to the solvent transfer unit 40, where the components 33 are moved down one by one so that flux 50 is transferred to each of the components 33. Attitudes of the electronic components 33 held by the nozzles 8 are picked up by the component image pickup devices 2a, 2b and measured, thereby judging the result. When the measured result of the held attitudes of the components 33 is normal, the components 33 are corrected in position on the basis of the obtained image information. Thereafter the XY robot 5 is moved and the electronic components 33 are mounted onto the circuit board.
As shown in FIGS. 14, 15, and 16, in an example of the conventional equipment, the electronic component mounting apparatus 10 has the transfer unit 40 of a type which rotates a transfer saucer 40b to form an approximately uniform film thickness of the flux 50. The operation of the prior art apparatus 10 after sucking the electronic components will be described in detail hereinbelow. The head part 6 having the nozzles 8 for sucking and holding the electronic components 33 is moved by the XY robot 5 to the solvent transfer unit 40 of the rotary transfer saucer type. The head part 6, when reaching the solvent transfer unit 40, lowers one of the plurality of sucked and held electronic components 33 to a transfer face of the transfer unit 40, whereby the flux 50 is transferred to the electronic component 33. After the electronic component 33 having the flux transferred thereto is moved up, the transfer saucer 40b is rotated by a motor 40d to make a thickness of the flux 50 approximately uniform with a blade 40a. Thereafter, the nozzle 8 sucking and holding the next electronic component 33 is moved by the XY robot 5 to a transfer position, and moved down to transfer the flux 50. The process is repeatedly carried out for all components 33. The head part 6 is moved to a desired mounting position after the flux 50 is transferred to all of the sucked and held electronic components 33, where the electronic components 33 are mounted.
In the thus-constituted conventional electronic component mounting apparatus 10 with the solvent transfer unit 40 of a rotary transfer saucer type, the flux is transferred to only one electronic component 33 at a time although a plurality of the electronic components 33 are sucked and held. As such, the volatile content of the flux 50 transferred to a first electronic component 33 already volatilizes at the time when the flux is transferred to a last electronic component 33, thus causing degradation in mounting quality. Mounting time is increased, which leads to deterioration in production efficiency.
Accordingly, the present invention is devised to solve these issues and has for its object to provide an apparatus and a method for mounting electronic components which can curtail a loss which would be brought about in a process wherein solvent is transferred to electronic components one by one.
In accomplishing these and other aspects, according to a first aspect of the present invention, there is provided an electronic component mounting apparatus comprising:
a component feed device for feeding a plurality of electronic components;
an object support device for holding and positioning an object to which the electronic components are to be mounted;
a plurality of component holding members for holding the electronic components from the component feed device and mounting the held electronic components to predetermined positions on the object;
a component image pickup device for measuring attitudes of the electronic components held by the component holding members; and
a flux transfer unit, comprising: a solvent transfer part for forming a film of a flux to be transferred to the components; and a film-forming blade for forming the solvent film at the solvent transfer part, for transferring the solvent to the electronic components by bringing the components held by the component holding members into contact with the solvent film simultaneously after the solvent film is formed by relatively and linearly sliding one of the solvent transfer part and the blade.
According to a second aspect of the present invention, there is provided an electronic component mounting apparatus according to the first aspect, wherein the solvent transfer unit has at the solvent transfer part a flat planar portion at which the solvent film is formed and has a driving part for relatively and linearly sliding one of the solvent transfer part and the film-forming blade, thereby regulating a film thickness of the solvent thereat through movement of the solvent transfer part or the blade thereby making the film thickness of the solvent approximately uniform.
According to a third aspect of the present invention, there is provided an electronic component mounting apparatus according to the first or second aspect, wherein the component feed device has cassette slots in which component feed cassettes, and the solvent transfer unit is capable of being inserted into one of the cassette slots of the component feed device to set the solvent transfer unit at the apparatus.
According to a fourth aspect of the present invention, there is provided an electronic component mounting apparatus according to any one of the first to third aspects, wherein in the solvent transfer unit, one of the solvent transfer part and the blade is slid in accordance with a component take-out signal indicating that the component is taken out by the component holding member from a component feed cassette attached at a cassette slot of the component feed device.
According to a fifth aspect of the present invention, there is provided an electronic component mounting apparatus according to any one of the first to fourth aspects, wherein the solvent transfer unit has the film-forming blade and a scraping blade for scraping unnecessary flux, and after the film of the flux is formed at the solvent transfer part by relatively and linearly sliding one of the solvent transfer part and the film-forming blade, the plural electronic components held by the component holding members are brought into contact with the film of the solvent to transfer the solvent to the held components, and after the solvent left at the solvent transfer part is scraped by the scraping blade, a new film of the solvent is formed at the solvent transfer part.
According to a sixth aspect of the present invention, there is provided an electronic component mounting apparatus according to any one of the first to fifth aspects, wherein the solvent transfer unit has a flat planar portion at the solvent transfer part, and when the solvent is transferred to the components, the solvent is transferred to bumps formed on electrodes of the plural electronic components while leveling the bumps by pressing the bumps against the flat planar portion of the solvent transfer part.
According to a seventh aspect of the present invention, there is provided an electronic component mounting method comprising:
relatively and linearly sliding one of a solvent transfer part and a film-forming blade in a flux transfer unit comprising the solvent transfer part at which a film of a flux to be transferred to electronic components is formed, and the film-forming blade for forming the solvent film at the solvent transfer part, thus forming the solvent film at the solvent transfer part; and
thereafter transferring the solvent to the electronic components by bringing the components held by component holding members into contact with the film of the solvent simultaneously.
According to an eighth aspect of the present invention, there is provided an electronic component mounting method according to the seventh aspect, further comprising regulating a film thickness of the solvent at the solvent transfer part through movement of the solvent transfer part or the blade, thereby making the film thickness of the solvent approximately uniform.
According to a ninth aspect of the present invention, there is provided an electronic component mounting method according to the seventh or eighth aspect, wherein the solvent film is formed by driving the solvent transfer part or the blade in accordance with a component take-out signal indicating that the component is taken out by the component holding member from a component feed device for feeding the components.
According to a tenth aspect of the present invention, there is provided an electronic component mounting method according to any one of the seventh to ninth aspects, further comprising, after the plural electronic components held by the component holding members are brought into contact with the film of the solvent to transfer the solvent to the held components, scraping the solvent left at the solvent transfer part by a scraping blade for scraping unnecessary flux, and then forming a new film of the solvent at the solvent transfer part.
According to an eleventh aspect of the present invention, there is provided an electronic component mounting method according to any one of the seventh to tenth aspects, wherein, when the solvent is transferred to the components, the solvent is transferred to bumps formed on electrodes of the plural electronic components while leveling the bumps by pressing the bumps against the flat planar portion of the solvent transfer part.